Damping device for snare-drums.



H. A. VAN VALKENBURG.

DAMPING DEVICE FOR SNARE DRUMS.

APPLICATION FILED FEB. 15. m5.

Patented Oct. 8, 1918.

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HAROLD A. VAN VALKENBURG, 0F OAKLAND, CALIFORNIA.

DAMPING DEVICE FOR SNARE-DRUMS.

Specification of Letters Patent.

Patented Oct. s, 1918.

Application filed February 15, 1915. Serial No. 8,169.

To all whom it may concern:

Be it known that I, HAROLD A. VAN VALKENBURG, a citizen of the United States, residing at Oakland, in the county of Alameda and State of California, have invented certain new and useful Improvements in Damping Devices for Snare- Drums, of which the following is a specification.

This invention relates to improvements in mechanisms used in connection with snare drums and more particularly to pneumatically operated drums of this character. iswell known the snares of drums of this character will vibrate when other notes having approximately the same wave length are sounded near the drum.

My invention relates to means for preventing these vibrations when the drum is not in use, the principal object being to provide a vacuum bellows for damping the snares whereby rapid changes inthe vacuum supply will not eflect the position of the damping device.

Another object of my invention is to flexibly mount the damping pad whereby the same may be always in uniform contact throughout the length of the snares.

With these and other objects in view my invention consists in the novel construction and combination of elementsas herein described and more specifically pointed out in the appended claims, and it will be understood that I do not limit myself to the showing made herein, but may adopt any variation within the scope of the claims.

Reference being had to the accompanying drawing forming a part of this specification,

Figure 1 is a view partly in elevation and partly in section of my improved device attached to a snare drum, and showing the means by which the same is operated.

Fig. 2 is a view in elevation of the drum showing my device applied thereon.

Fig. 3 is a view in plan of the vacuum bellows employed in connection with my invention showing the portion thereof in section.

Fig. 1 is an enlarged sectional View on 4-4, Fig. 3.

Denoting corresponding parts by the same numerals of reference, 1 is the snare drum having the heads 2 and 3 on the latter of p which rests snares 4. A bar 5, is attached to the hoop 17 of the drum and serves as a support for the vacuum bellows 6. The latter consists of the stationary side 7 attached to bar 5 by means of screws 8, and the movable side 9 having attached thereto a strip 10 slightly shorter than the diameter of the drum, this strip 10 is provided with a felt or other soft ad 11 ada ted to rest on the snares 1, and is held on t e snares by means of springs 13, these springs consisting of a loop 14 and the ends 15 and 18 extending therefrom at right angles to each other. The end 15 is fixed in the outer edge of hoop 17 while the other end 18 extends to the center of strip 10 where it is curved downwardly and rests in a depression 19 in the surface of this strip. By this method of mounting the strip is held upon the snares and at the same time is capable of accommodating itself in any plane.

Mounted on the back of the bellows 6 is a small chest 20 having an outlet connection 21. This chest communicates with the interior of bellows 6 by means of openings 22 and 23, the latter being very small and in the nature of a bleed hole. Over the opening 22 within the chest is placed a flexible strip 2 1, which is fastened only on its two ends as shown at 25. By this means when the chest 20 is connected with means for exhausting the same strip 24 is raised as shown at Fig. 4, which allows the bellows 6 to become exhausted.

Denoted by 27 is a device for vibrating drum stick 28. The particular construction of this device is immaterial to the present invention, it being sufficient to state that it is so constructed that the bellows is alternately connected with the atmosphere and with the source of vacuum to cause the part thereof which carries the drum stick 28 to be oscillated, to beat the drum. Connection with the source of vacuum is made through the pipe 29, from which the branch 30 leads to the chest 20. 30 denotes a pneumatically operated valve which serves to connect the pipe 29 to pipe 42 leading to a source of vacuum. This valve consists of the valve chamber 31, the vacuum chamber 32, the latter, connecting with the former through the openings 33. The valve 34 within the former is operated by means of a stem 3 1 resting on the diaphragm 35. Atmospheric pressure is admitted under this diaphragm either manually through the key 36 or automatically through an opening in the music roll 37. The key 3.6 is normally closed and if the drum is to be operated automatically the valve 89 is shifted to the left in order to place the passage from the music roll in communication with the cell of diaphragm 35. Thus whenever the atmospheric pres sure is admitted to this cell either through the tube 40 or 41, the diaphragm 35 is raised the valve 34 is un'seated and the air is exhausted through pipe 29 from the bellows 6 and bellows 27. As soon as the bellows 6 is exhausted the strip 10 is raised from the snares and when the bellows 27 is exhausted the movable side collapses and a blow is.

struck on the front drum head by the stick 28. Immediately air is admitted to the bellows 27 through suitable valve means and the bellows expands whereby the passage to the atmosphere is cut off and the bellows again collapses as long as the air is exhausted through the tube 29.

It will be apparent that when the atmospheric pressure is admitted to allow the bellows 27 to expand the tendency would be to decrease the vacuum in pipe 29 and thus allow the bellows 6 to inflate thus damping the vibrations of the snares between the strokes of the drum stick. This, however, is not desirable and for this reason the flexible valve strip 24 is provided. As soon as the pressure in the chest 20 tends to rise this strip closes the opening 22 thus holding the bellows collapsed and the pad from the snares. This holding action is not continued definitely. on account of the small opening 23, which allows the bellows to become slowly inflated. The construction is such, however, that the pad is held from the snares between the different strokes of the drum stick and is only lowered thereon after the same has ceased to operate. 1

lVhen the key is released or the opening in the music roll 37 is closed pressure is equalized on the two sides of the diaphragm and valve 40 closes allowing the atmospheric pressure to enter tube 29 and 30 and thus inflate the bellows 6. The springs 13 depress the strip to hold the pad on the snares until the key or the music roll again operates the device.

It will thus be seen that I have provided an improved device for damping the vibrations of the drum snares when the same is not being played, but which allows the full vibration thereof between the various strokes of the drum stick while the drum is being played.

\Vhat I claim as new and wish to cover b Letters Patent is 1. The combination with a drum and the snares thereof, of pneumatically-operated damping mechanism for the snares, collapsi- Copies of this patent may be obtained to! ble, and operating to free the snares, upon applying suction to said mechanism, a conduit adapted to connect a source of vacuum with said mechanism, means to produce relatively rapid changes in the vacuum of the conduit, and valve mechanism in said conduit operating to permit the suction in said conduit to collapse said mechanism and prevent relieving of the vacuum in the latter during the relatively rapid changes in the degree of vacuum in said conduit.

2. The combination with a drum and the snares thereof, of pneumatically-operated damping mechanism for the snares, collapsible, and operating to free the snares, upon applying suction to said mechanism, means adapted to connect a source of vacuum with said mechanism, means to produce relatively rapid changes in the vacuum of the conduit, and valve mechanism in said first-named means involving a main passage and a bleed passage, both in communication with said first-named means and with said first-named mechanism and through which suction on the latter is effected, and a check-valve cooperating with said main passage and operating to close the latter and prevent reinflation of said first-named mechanism through said last-named passage, whereby under relatively rapid fluctuations in the degree of vacuum, the first-named mechanism remains deflated.

3. The combination with a drum and the snares thereof, of pneumatically-operated damping mechanism for the snares, collapsible, and operating to free the snares, upon applying suction to said mechanism, a conduit adapted to connect a source of vacuum with said mechanism, a second mechanism operated by the suction in said conduit and connected with the latter between the point of application of the vacuum to said conduit and said first-named mechanism and producing, in its operation, relatively rapid changes in the degree of vacuum in said conduit, a valve mechanism in said conduit between said first-named mechanism and the connection of said second mechanism with said conduit, operatin to permit the suction in the conduit to col apse said first-named mechanism andprevent relieving of the vacuum in the latter during the relatively rapid changes in the degree of vacuum produced in said conduit by the operation of said secondnamed mechanism,

In testimony whereof I afiix my signature in presence of two witnesses.

' HAROLD A. VAN VALKENBURG. lVitnesses:

S. D. GIBBEL, W. A. S'rocx.

live cents each, by addressing the Commissioner of Patents,

Washington, I). O. u 

